Currently, search engines are used to search large networks, such as the internet, for textual documents that are relevant to a user. Typically, the user types in one or more query words and the search engine accesses an inverted index to locate the network documents that contain the words.
Some search engines are available that allow the user to search for audio documents or video documents that contain audio signals. In order to perform this search function, the search engine first performs speech recognition on the audio signal to form a string of words represented by the audio signal. The string of words is then indexed.
Because speech recognition is imperfect, the documents identified by the search engine may not actually contain the search query terms.
The discussion above is merely provided for general background information and is not intended to be used as an aid in determining the scope of the claimed subject matter.